Portable elevator



Aug. 7, 1956 E. A. WHITE, JR 2,757,755

PORTABLE ELEVATOR Filed Sept. 13, 1952 ATTORNEYS United States Patent O PORTABLE ELEVATOR Edward A. White, Jr., Mahwah, N. J., assigner to United Hoisting Company, Englewood, N. J., a corporation Application September 13, 1952, Serial No. $095,398 Claims. (Cl. IS7- 2) This invention relates to portable elevators and, more particularly, to portable elevators which can be delivered to the site of and raised into operative position adjacent a building structure.

In the course of erection of large building structures, and often in the case of alteration of such structures, there is need for an elevator for lifting building materials and supplies to the upper levels of the building. The most common expedient in the past has been the construction on the site of an elevator shell or frame in which a lifting platform is positioned for raising material above ground iloor levels. The construction of such an elevator structure is both expensive and time consuming, and consequently there have been proposed and built heretofore portable elevator structures which can be delivered to and raised at the building site. A

dominant limitation on the shape and structure of such portable elevators has been the height of tunnel and bridge openings through which such a portable elevator must frequently pass in being brought to the building site. As a result of this limitation, the most practical portable elevator structure developed heretofore has been in the form of a tower which can be transported in its horizontal position, but not completely assembled with other components of the elevator, and then assembled and raised at the building site. An externally positioned lifting platform is carried by such a tower for lifting materials to upper building levels. Because of the exterior positioning of the elevator platform, there is considerable danger of workmen and materials falling off the open sides of the platform, a hazard which in many states has necessitated building around the base of the tower a substantial overhead structure to protect the workmen.

I have now devised a portable elevator structure which not only can be readily delivered to and raised at any building site but is also characterized by the safer elevator structure represented by a shell or framework which encloses the elevator platform. Because of the novel mounting of this structure in its horizontal inoperative position on a trailer unit and by virtue of its novel raising mechanism, there is hereby made available to the art a completely assembled elevator structure with enclosed lifting platform which, in its inoperative and traveling position, does not exceed a height (generally about twelve and one-half feet) corresponding to the minimum height of bridge and tunnel openings.

The portable elevator of my invention comprises a wheeled trailer frame, an elevator shell and an elevator platform positioned within the elevator shell. The elevator shell is supported in its inoperative horizontal position on the trailer frame with the upper operative end of the shell resting on the forward end of the trailer frame and with the lower operative end of the shell projecting beyond and being supported adjacent the rearward end of the trailer frame. A pivot arm is connected at its pivoted ends respectively to a forward portion of the trailer frame and to the lower portion of the elevator shell inwardly from the lower operative end thereof but beyond the rearward end of the trailer frame. The lower portion of the lower operative end of the elevator is advantageously provided with a rolling element, and a raising cable interconnects a winch mounted on the trailer frame with this same lower portion of the lower operative end of the elevator shell. Thus, when the raising cable is wound on the winch, the cable pulls the lower operative end of the elevator shell downwardly and inwardly toward the rearward end of the trailer frame and thus raises the elevator shell to its operative elevated position about a pivot point comprising the junction of the pivot arm and the elevator shell.

These and other novel features of the elevator structure of my invention will be more readily understood from the following discussion taken in conjunction with the drawings in which Fig. l shows the portable elevator structure of the invention in its inoperative position for delivery to a building site; l

Fig. 2 shows the elevator structure in an early stage of its being raised at the site;

Fig. 3 shows the elevator in a later raising stage; and

Fig. 4 shows the elevator raised to its nal operative position.

The portable elevator, as shown in Fig. 1, includes a low-slung trailer frame 5 the rear end of which is provided with wheels 6 and the forward end of which is` provided with a conventional mounting device 7 which connects it to a standard motor-driven tractor unit. Carried by this trailer frame is a completely assembled elevator structure or shell 8 composed of tubular or other structural frame members and provided with elevator platform guides 9. The upper operative end 10 of the elevator shell, that is, the end ofthe shell which is uppermost when the shell is raised to its operative position, `is supported adjacent the forward end of the trailer frame by an upstanding supporting arm 11 mounted on the trailer frame. The lower operative end 12 of the elevator shell, that is, the end of the shell which is lowermost when the shell'is raised to its operative vertical position, is supported by a similar upstanding supporting arm 13 adjacent the rearward end of the trailer frame. I have found it advantageous to secure the forward supporting arm 11 to the frame `and merely allow the elevator shell 8 to rest thereon and to secure the rearward supporting arm 13 to the frame of the shell so that the lower end of the arm 13 bears against and is supported by the trailer frame 5. Of course, this arrangement may be reversed or both shell-supporting arms 11 and 13 may be of either of the aforementioned forms. Both forms of supporting arms function satisfactorily with the raising mechanism of my novel elevator structure.

The raising mechanism of the portable elevator of my invention comprises a pivot arm 14 which is pivotally connected to a suitablebracket near the forward end of the trailer frame with the other end of the arm pivoted to a bracket 16 secured to the elevator shell. The pivotal connection between the arm 14 and the bracket 16 on the elevator 'shell is positioned beyond the rearward end of the trailer frame but is also positioned inwardly from the lower operative end 12 of the elevator shell. The relationship between the length of the pivot arm 14 and the position of its pivoted ends on the trailer frame and on the elevator shell is such that when the shell is raised to its vertical operative position shown in Fig. 4 the lower operative end 12 of the shell will be brought directly into contact with thev end of the trailer frame. The remainder of the raising mechanism comprises a hand-V winch 17 operated bya handle 1S and a raising cable 20 interconnecting the winch and the lower operative end of the elevator shell inV order to obtain maximum leverage about the pivot point represented by the bracket 16. I have found it advantageous to direct the raising cable 20 from the hand-winch 17 positioned low on the trailer frame to a pulley 21 near the lower operative end of the shell and with the leverage strands of the raising cable 20 interconnecting this end pulley 21 and a multi-sheave pulley 22 mounted on a supporting frame 23 above the winch 17.

The portable elevator structure further includes a lift platform 24 having a lifting frame 25 positioned within the elevator shell 8 and preferably located at the lower operative end 12 of the shell during transit. The platform frame 25 is connected by a lift cable 26 which passes over conventional lift pulleys 27 and 28 in the upper operative end 10 of the elevator shell and thence to a power-driven winch 30 mounted on tnc trailer frame. As an aid to raising the elevator shell, l have found it advantageous to secure to the pivot arm 14 near its outboard end a supporting leg 31 which is held in raised position parallel to the pivot arm during transit by a suitable lock-clamp 32 and which may be lowered to the dotted position indicated in Fig. 1 so as to support the outboard end of the pivot arm when the raising cable 20 is tightened for raising the shell to its operative position.

After delivery of the portable elevator trailer to the building site where it is to be raised, the trailer is moved into the elevator-raising position which, in turn, is generally determined by the position of the elevator shell loading openings. For example, if the shell is provided with a structural network along its two lateral sides as indicated in the drawings, the top or bottom sides (or both) of the elevator shell in its horizontal position may be provided with a more open structure to permit loading and discharging of men and material through the side of the shell. Of course, the relatively open sides of the elevator shell may be reversed from that shown in the drawing, that is, they may be positioned on the lateral sides of the shell. When an open loading face for the elevator shell is formed along the top side of the shell when the latter is in its horizontal or inoperative position, the trailer is preferably backed into a position immediately adjacent the building structure along which the elevator is to be raised. The pivot arm supporting leg 31 is then released from its clamped position shown in Fig. 1 to the vertical position indicated by the dotted lines in Fig. 1, and if the base of the supporting leg does not touch the ground wooden boards or blocks may be used to till the space between the base of the leg 31 and the ground. The winch handle 18 is then turned to pull the raising cable 20, and as the cable is taken up on the winch 17 the lower operative end 12 of the elevator shell is pulled downwardly and the upper operative end of the shell is raised about the pivot point represented by the bracket 16, all as shown in Fig. 2. As the raising cable 20 is further taken up on the winch 17, the lower operative end of the elevator shell is pulled toward the trailer and this movement of the shell along the ground, as shown in Fig. 3, is facilitated by rolling element 33 mounted on the lower edge of the shell. If it is desired to raise the elevator shell immediately adjacent the exterior surface of the building structure, it is advantageous during the shell-raising operation to progressively move the trailer rearward as the shell is being raised so that the relative movement between the lower operative end 12 of the shell and the rear end of the trailer is provided by movement of the trailer rather than by movement of the shell Iaway from the building structure. The raising cable 20 is further wound up on the winch 17 until the elevator shell has been raised to the vertical position indicated in Fig. 4. It will be noted that as the shell is raised from the position shown in Fig. 2 to that shown in Fig. 4 the upper end of the pivot arm 14 adjacent the shell is continuously raised so that when the shell is in its vertical position the pivot arm 14 will serve as a supporting brace to hold it firmly in its raised position.

During raising of the elevator shell as described hereinbefore, a guide cable 19 is advantageously connected between the upper operative end of the shell to a hand winch 29 on the forward end of the trailer frame. In this way it is possible to control positioning of the upper end of the shell as it approaches its vertical position and thereby prevent the shell from rocking past the vertical position and striking the building structure.

ln order to make the portable elevator unit self-sufficient in the absence of the motor-driven tractor which carries it to the building site, the forward end of the frame is advantageously provided with a crossbeam 35 which extends slightly outboard of the frame on both sides thereof. Blocks of wood 36 (or jacks if desired) may be positioned below the outboard ends of the beam 35 so as to support the forward end of the trailer frame in the absence of the tractor unit. A similar crossbeam 37 is provided nearer the rearward end of the trailer frame so that blocks of wood or a jack 38 may be positioned thereunder in order to correct any lateral tilting of the elevator shell due to sloping of or irregularities in the surface of the ground on which the wheels of the trailer frame rest.

It will be appreciated, accordingly, that the elevator structure of my invention is not only portable but is self-contained in every respect including its complete enclosure of the lift platform. All this has been accomplished while neverthless maintaining a structure which is capable of being moved through all standard height bridges and tunnels so that the portable elevator may be delivered to virtually any building site. lt will also be appreciated that the elevator shell may be raised at the building site to its operative vertical position by a single man and that it does not require any structural rearrangement or completion during this raising to operative position.

I claim:

l. A portable elevator adapted to be delivered to the side of and raised into operative position adjacent a building structure, the elevator comprising a wheeled trailer frame, an elevator shell, an elevator platform positioned witliin the elevator shell, shell-supporting means positioned adjacent the forward and rearward ends of the trailer frame for supporting the shell in its inoperative horizontal position on the trailer frame with the upper operative end of the shell resting on the forward end of the trailer frame and with the lower operative end of the shell projecting beyond and being supported adjacent the rearward end of the trailer frame, a pivot arm pivotally connected at its ends respectively to a forward portion of the trailer frame and to the lower portion of the elevator shell inwardly from the lower operative end thereof but beyond the rearward end of the trailer frame, a winch mounted on the trailer frame, and a cable interconnecting the winch and the lower portion of the lower operative end of the elevator shell and thereby adapted,` when the cable is wound on the Winch, to pull the lower operative end of the elevator shell initially downwardly about theshell-supporting means adjacent the rearward end of the trailer frame until it makes contact with the ground and thereafter inwardly toward the rearward end of the trailer frame about the pivotal connection between the pivot arm and the lower operative end of the elevator shell and thus raise the elevator shell to its operative vertical position.

2. A portable elevator adapted to be delivered to the site of and raised into operative position adjacent a building structure, the elevator comprising a wheeled trailer frame, an elevator shell, an elevator platform positioned within the elevator shell, shell-supporting means positioned adjacent the forward and rearward ends of the trailer frame for supporting the shell in its inoperative horizontal position on the trailer frame `with the upper operative end of the shell resting on the forward end of the trailer frame and with the lower operative end of the shell projecting beyond and being supported adjacent the rearward end or the trailer frame, a pivot arm pivotally connected at its ends respectively to a forward portion of the trailer frame and to the lower portion of the elevator shell inwardly from the lower operative end thereof but beyond the rearward end of the trailer frame, the lower portion of the lower operative end of the elevator being provided with a rolling element, a winch mounted on the trailer frame, and a cable interconnecting the winch and the lower portion of the lower operative end of the elevator shell and thereby adapted, when the cable is wound on the winch, to pull the lower operative end of the elevator shell initially downwardly about the shell-supporting means adjacent the rearward end of the trailer frame until it makes contact with the ground and thereafter inwardly toward the rearward end of the trailer frame about the pivotal connection between the pivot arm and the lower operative end of the elevator shell and thus raise the elevator shell to its operative vertical position.

3. A portable elevator adapted to be delivered to the site of and raised into operative position adjacent a building structure, the elevator comprising a wheeled trailer frame, an elevator shell, an elevator platform positioned within the elevator shell, the shell being supported in its inoperative horizontal position on the trailer frame with the upper operative end of the shell resting on the forward end of the trailer frame and with the lower operative end of the shell projecting beyond and being supported adjacent the rearward end of the trailer frame, a pivot arm pivotally connected at its ends respectively to a forward portion of the trailer frame and to the lower portion of the elevator shell inwardly from the lower operative end thereof but beyond the rearward end of the trailer frame, the portion of the pivot arm adjacent its junction with the elevator shell being provided with a supporting leg adapted to make supporting contact with the ground while the shell is in its inoperative horizontal position, the lower portion of the lower operative end of the elevator being provided with a rolling element, a winch mounted on the trailer frame, and a cable interconnecting the winch and the lower portion of the lower operative end of the elevator shell and thereby adapted, when the cable is wound on the winch, to pull the lower operative end of the elevator shell initially downwardly about said supporting lug and thereafter inwardly toward the rearward end of the trailer frame about the pivotal connection between the pivot arm and the lower operative end of the elevator shell and thus raise the elevator shell to its operative vertical position.

4. A portable elevator adapted to be delivered to the site of and raised into operative position adjacent a building structure, the elevator comprising a wheeled trailer frame, an elevator shell, an elevator platform positioned within the elevator shell, shell-supporting means positioned adjacent the forward and rearward ends of the trailer frame for supporting the shell in its inoperative horizontal position on the trailer frame with the upper operative end of the shell resting on the forward end of the trailer frame and with the lower operative end of the shell projecting beyond and being supported adjacent the rearward end of the trailer frame, a pivot arrn pivotally connected at its ends respectively to a forward portion of the trailer frame and to the lower portion of the elevator shell inwardly from the lower operative end thereof but beyond the rearward end of the trailer frame, the lower portion of the lower end of the elevator being provided with a rolling element, a winch mounted on the trailer frame, a cable interconnecting the winch and the lower portion of the lower operative end of the elevator shell and thereby adapted, when the cable is wound on the winch, to pull the lower operative end of the elevator shell initially downwardly about the shell-supporting means adjacent the rearward end of the trailer' frame until it makes contact with the ground and thereafter inwardly toward the rearward end of the trailer frame about the pivotal connection between the pivot arm and the lower operative end of the elevator shell and thus raise the elevator shell to its operative vertical position, a power-driven winch mounted on the trailer frame, and a lifting cable interconnecting the power-driven winch and the elevator platform and adapted to lift the platform within the elevator shell when the shell is raised to its vertical operative position.

5. A portable elevator adapted to be delivered to the site of and raised into operative position adjacent a building structure, the elevator comprising a wheeled trailer frame, an elevator shell provided with at least one side wall structure having openings for loading and unloading of an elevator platform within the shell, an elevator platform positioned within the elevator shell, shell-supporting means positioned adjacent the forward and rearward ends of the trailer frame for supporting the shell in its inoperative horizontal position on the trailer frame with the upper operative end of the shell resting on the forward end of the trailer frame and with the lower operative end of the shell projecting beyond and being supported adja cent the rearward end of the trailer frame, a pivot arm pvotally connected at its ends respectively to a forward portion of the trailer frame and to the lower portion of the elevator shell inwardly from the lower operative end thereof but beyond the rearward end of the trailer frame, the lower portion of the lower operative end of the elevator being provided with a rolling element, a winch mounted on the trailer frame, and a cable interconnecting the winch and the lower portion of the lower operative end of the elevator shell and thereby adapted, when the cable is wound on the winch, to pull the lower operative end of the elevator shell initially downwardly about the shell-supporting means adjacent the rearward end of the trailer frame until it makes contact with the ground and thereafter inwardly toward the rearward end of the trailer frame about the pivotal connection between the pivot arrn and the lower operative end of the elevator shell and thus raise the elevator shell to its operative vertical position.

References Cited in the le of this patent UNITED STATES PATENTS 801,372 Foltz Oct. 10, 1905 1,853,086 Scannell Apr. 12, 1932 2,331,559 McEwen Oct. 12, 1943 2,344,390 Cohen Mar. 14, 1944 2,611,580 Troche et al. Sept. 23, 1952 

